Every day scientists use the world’s best telescopes to unlock the secrets of the cosmos. Yet, fundamental questions remain unanswered. What is dark matter/energy? Is Earth the only home for life? Not even the grand Hubble Space Telescope has been able to answer these questions. It’s working on it, though.
Astronomers are excited about what the next generation of telescopes will tell us about our place in the universe. Many of you know about the James Webb Space Telescope, but NASA is working on more. Yesterday, the space agency announced the Wide Field Infrared Survey Telescope (WFIRST) is no longer just a study. It’s moving ahead into project phase and should launch in about a decade.
What is the Wide Field Infrared Survey Telescope?
In many ways, it’s not that different from the Hubble Space Telescope. The image quality will be about the same as the Hubble. But what makes it special can be found in its name – ‘wide field.’ That single image may be the same quality as the Hubble, but its field of view will be 100 times greater.
Here’s an example of a Hubble survey.
The Hubble needed to be pointed 432 times for this survey. Now look at what WFIRST will be able to do.
Just two. And remember, WFIRST is just as powerful as the Hubble. It will give astronomers more info then they can handle. Discoveries from WFIRST will likely continue long after its mission ends.
WFIRST also carries a Coronagraph Instrument. Ever wonder how scientists expect to figure out the makeup of an exoplanet’s atmosphere? This is it. The instrument will block the blinding glare of host stars and reveal the faint light of the planets orbiting them.
By observing the light from the planets, scientists should be able to figure out the chemical makeup of the atmosphere. Armed with atmospheric data from scores of exoplanets, scientists will be able to better understand where these atmospheres came from and how they formed. And ultimately, expand the search for planets suitable for life.
Paul Hertz, director of NASA’s Astrophysics Division in Washington, reiterates the importance of WFIRST. “WFIRST is designed to address science areas identified as top priorities by the astronomical community,” he said. “The Wide-Field Instrument will give the telescope the ability to capture a single image with the depth and quality of Hubble, but covering 100 times the area. The coronagraph will provide revolutionary science, capturing the faint, but direct images of distant gaseous worlds and super-Earths.”
While the coronagraph focuses on the smaller details, the telescope’s wide field view will try to answer one of the biggest questions. What is dark matter/energy?
How will WFIRST try to tackle this long-standing question? The telescope will measure the distances of thousands of supernovae. It can also figure out the shapes, positions and distances of millions of galaxies. This data will aid scientists looking into dark matter by mapping the distribution and growth of the universe.
It’s easy to focus on the exoplanets and dark matter, but WFIRST will do much more. “In addition to its exciting capabilities for dark energy and exoplanets, WFIRST will provide a treasure trove of exquisite data for all astronomers,” said Neil Gehrels, WFIRST project scientists. “This mission will survey the universe to find the most interesting objects out there.”
When will WFIRST launch? Right now, it’s expected to head into Earth orbit in the mid-2020s.
WFIRST will join the James Webb Space Telescope and other telescopes at the second Lagrange point (L2). There’s another keyword in WFIRST’s name. Infrared. Orbiting at the L2 point keeps the telescope shielded from bright sources (the sun) as it looks for faint infrared signals in the sky.
Here’s an image of the five Lagrange points.
These five orbital points allow objects to stay relatively stationary thanks to the gravity from the Earth and the Sun. L2 is a great spot to park telescopes that observe in infrared. Alternatively, L1 is where space agencies park their sun-observing satellites.
Over the course of its mission life, WFIRST will measure the light from a billion galaxies and find an estimated 2,600 exoplanets.
Image credits: NASA